Annealing furnace



Nov. 25, 1930. GB. SHIPLEY ET AL ANNEALING FURNACE Filed Jan. 4, I929 4Sheets-Sheet l 5 E 5 s E N W w Nov. 25, 1939- G. B. SHIPLEY ET AL1,782,481 ANNEALING FU Filed Jan. 4, 1929 4 Sheets- Sheet 2 INVENTOR 774-4 I At Mat Noi 25-, 1930. a. B. SHIPLEYET AL" I 1,782,431

ANNEALING FURNACE:

Filed Jan. 4, 1929 4 Sheets-Sheet 5 WITNESSES Nov. 25, 1930. GL'B.SHIPLEY ET AL ANNEALING FURNACE I Filed Jan. 4, 1929 4 Sheets-Sheet 4INVENTORS gll Patented Nov. 25, '1930 UNITED STATES GRANT B. SHIPLEY ANDHENRY ALINDEB I, OF PITTSBURGH,

PATENT OFFICE PENNSYLVANIA, .AS-

SIGNORS, BY MESNE ASSIGNMENTS, TO THE INTERNATIONAL NICKEL COMPANY,

me, or NEW Yonx, N. Y., A

CORPORATION OF DELAWARE ANNEALING rummcn Application filed January 4,1929. Serial No. 330,173.

This invention relates to annealing furing elongate metal stock such astubes, rods, and the like. u

The object of the invention generally stated is to provide a simple,compact and automatically operable furnace in which elongated stock suchas metal tubes may be'uniformly and rapidly annealed as they are pro- 30gressively moved through the furnace.

he inventionis described in conjunction with the accompanying drawings,which illustrate its preferred embodiment, and in which Fig. 1 isa-transverse vertical sectional view of the furnace; Fig. 2 a verticalsection taken longitudinally through the furnace on theline II II ofFig. 1; Fig. 3 a horizontal sectional view on the line IIIIII of Fig.

1; and'Fig. 4: a vertical section to enlarged scale taken transverselythrough a portion of v ghe furnace along the broken line IV-IV, ig. 3.

The annealing furnace provided according to the invention comprises asingle upright chamber having a bafiie extending longitudinally throughits center, which divides the chamber into front and rear compartments.The front compartment is provided with heating means such as electricalheating units, and the rear compartment is provided with'cooling meanssuch' as a water jacket through which water is circulated to rapidlyabsorb heat. Thus heating and cooling zones are provided in the furnace.Tubes or the like are fed laterally into the heating zone by an endlessconveyor arranged along the front wall of the furnace, a longitudinalinlet opening jacent the lower end of the heating compartment.

Inside'the furnace, and supported in the baflie structure, there isanother conveyor which receives the tubes as they enter the furnace andcarries them upwardly through 5 the heating compartment where they areheated. then over the bafiie and downwardly through the cooling zone,where their heat is rapidly absorbed by the water in the Water jacketswhich preferably form the walls of this compartment. At the bottom ofthe coolnaces, and especially to furnaces for anneal-' discharged fromthe furnace.

being arranged in such wall ading compartment there is arranged alongitudinal opening through which the tubes are The furnace is enclosedon all sides to prevent the heat and atmosphere in the annealing chamberfrom escaping, and the openings through which the tubes are fed into anddischarged from the furnace are provided with doors adapted to be openedand closed whenever material is passed through them. a

Referring now to the drawings, the furnace is illustrated as comprisinga single elongated upright chamber structure supported upon a foundation1 and having its front wall 2, end walls 3 and 4, top 5 and the upperportion 6 of its back wall constructed of heat insulating material suchas fire brick, the lower portion of its rear .wall being formed out of aplurality of water jackets 7. The furnace is divided into twocompartments by means of an inverted U-shaped bafile structure 8extending longitudinally of the furance and upwardly to-near the top ofthe chamber. This bafil-e is constructed similar to the furnace walls,having its front 76 wall and top constructed of fire brick or the" like,and its back wall formed of a plurality of water jackets 9. In the frontcompart ment of the furnace, and preferably attached to the front wall,are a number of electrical heating elements v10 employed to heat thetubes as as they are passed upwardly through the furnace. It will beunderstood however that any other suitable heating units may be employedfor this purpose if desired. By placing a bafiie structure 8 in thecenter of the chamber in the manner illustrated, and by providingheating elements in one of the compartments formed by the baffle andwater jackets in the other, adequate heating and cooling zones areprovided in the furnace.

In order .to feed elongated blanks such as tubes laterally into thefurnace a conveyor 11 is arranged adjacent its front wall 2. Thisconveyor may consist of a number of endless chains 12 extending aroundsprockets 13 and 14 (Figs. 1 and 4) secured to rotatable shafts 15 and16, respectively, supported by a frame 17. For operating conveyor 11independently of the rest of the furnace, an electric 100 motor 18 iscoupled to a reduction unit 19. A sprocket wheel 20 is mounted on thedrive shaft of this reduction uni! and a chain 21 is passed around itand over a sprocket wheel 22 loosely mounted on conveyor shaft 15. Aclutch coupling 23 is slidably mounted on shaft 15 which is adapted tobe moved into engagement with sprocket wheel 22 and thereby effect ihemovement of the conveyor.

Along the front of the furnace at the point where tubes are dischargedfrom conveyor 11, and on a level with the bottom of the an to its rotora sprocket wheel 29 which engages a chain 28 passing around a sprocketwheel 31 mounted on stub shaft 26.

' The upper curved surface of door 25 is sealed by means of a flexibleapron 32 which effectively prevents gas leaking out around the door whenit is closed, and to prevent the tubes jamming against the door as theydrop off conveyor 11, latch arms 33 are provided. These arms are mountedon a shaft 34 sup ported in the furnace frame immediately 111 front ofthe door, and by means of connecting rods 35 are moved simultaneouslywith door 25, thus permitting the tubes to pass into the furnace whenthe door is opened and preventing them from jamming the door when it isclosed.

On the inside of the furnace there is provided an endless conveyor 36for carrying the tubes from the charging inlet upwardly through theheating zone, past the heating elements 10, over the top of bafflestructure 8, downwardly through the cooling zone past water jackets 7and '9 where their radiated heat is absorbed, and to an outlet ordischarge opening 37 running longitudinally along the back of thefurnace. lhis conveyor comprises a plurality of link belts 38 mounted inspaced relation along the length of baflie 8 and adapted to move invertical openings formed in the bafile structure. The linksof thesebelts are provided with fingers 40. the outer ends of which have pairsofjaws forming pockets which extend outside of the bafile wall and inwhich the tubes are cradled as they are passed through the furnace.Suitably supported in the top of the baffle structure opposite each ofits openings 39 is a sprocket wheel 43. and suitably supported inthebottom of the baffle structure there is provided a shaft 41 uponwhich a plurality of sprocket wheels 44 are mounted in alignment withsprocket wheels 43. About the super posed pairs of wheels 43 and 44 thebelts 38 are mounted with the outer ends of its conveyor fingersextending outwardly through openings 39. To actuate conveyor 36, a motor48 is coupled to a reduction unit 49. on the drive shaft of which thereis secured a sprocket wheel 51 around which there extends a chain 52which passes over a sprocket wheel keyed to shaft 41. Hence when 1110-tor 48 is actuated the inner conveyor is moved upwardly through theheating and downwardly through the cooling zones of the furnace.

'The fingers on each of the conveyor belts are arranged in alignmentwith those on every other belt, and by bringing conveyor 36 to rest witha row of fingers registering with lower surface 54 of charging opening24, Figs. 1 and 4, door 25 may be raised and a tube passed into thefurnace and rested in the pockets in the outer ends of the conveyorngers. In charging the furnace each row of fingers is stopped inalignment with opening 24 and one or more tubes passed through door 25into them.

. To normally operate both conveyors 11 and 36 by means of motor 48, asecond sprocket wheel 55 is arranged on the drive shaft of reductionunit 49, and from this sprocket wheel a chain 56 is passed around asprocket wheel 57 loosely mounted on conveyor shaft 15 alongside clutchcoupling 23. This .sprocket wheel is adapted to be engaged by clutchcoupling 23 in the same manner as is sprocket 22. Hence the feedingconveyor may be actuated by either motor 18 or motor 48. Motor 18 isemployed primarily for actuating conveyor 11 independently of the restof the furnace so that it may be loaded with tubes before thefurnace ischarged.

To discharge the tubes from the furnace after they have been passedthrough the heating and cooling zones, arms 58 are arranged in the lowerportion of the cooling zone in such a way that they pick the tubes outof the pockets in the outer end of fingers 40 and cause them to slideinto discharge opening 37 where they are engaged by latch arms 59arranged in the opening to prevent the tubes jamming against door 61.WVhen door 61 is opened, latch arms 59 are actuated by connecting'rods62 permitting the tubes to pass out of the furnace. Stub shafts 63 arepro vided at opposite ends of door 61, and by means of them door 61 ismounted in the furnace frame in the same manner as door A motor isarranged adjacent the end of the furnace for operating door 61. On thedrive shaft of this motor there is mounted a sprocket wheel 64 aroundwhich a chain 65 is provided which extends around a sprocket wheel 66mounted on stub shaft 63. Hence door 61 is opened and. closed in thesame fashion as door 25 to discharge tubes from the furnace. To preventa draft passing through the furnace when material is being entered intoor taken out of it, doors 25 and 61 are arranged to open at differenttimes and preferably in succession, door 61 being actuated by theclosing of door 25.

In operating the furnace it is preferably charged with a suitablenon-oxidizing atmosphere, and the heating elements heated until theproper temperature is attained. Feeding conveyor 11 is then set inmotion by placing clutch coupling 23 in engagement with sprocket wheel22 and starting motor 18. After the feeding conveyor has been loadedwith tubes to a point where it discharges them into inlet opening 24,coupling clutch 23 is moved into engagement with sprocket wheel 57 andmotor 48 is started. With the starting of motor 48, conveyors 36 and 11are set in motion. When a row of fingers on con-' veyor 36 are inregistration with the lower end of surface 54 forming the bottomof inletopening 24, the motor is stopped. Door 25 is then actuated by motor 27to admit one or more tubes to the furnace. Motor 48 is again started andthe next row of fingers brought into alignment with the inlet opening24. Conveyor 11 being operated simultaneously by the same motor asconveyor 36, tubing is deposited in the inlet opening as the precedingtubing is being raised and as the next row of fingers on conveyor 36 isbeing brought into alignment with the inlet opening. This operation ofloading the inner conveyor is repeated each time a row of fingersregisters with opening 24, and thus the tubes are progressively andcontinually assed through the furnace stepby-step. hen the annealedtubes reach the lower portion of the cooling chamber they are raisedoutof the pockets in the ends of fingers 40 by means of arms 58 andcarried to discharge openings 37 where they pass from the furnace by theopening of door 61, which takes place when motor is set in motion.

In order to have motors 48, 27 and 60 autoinatically actuate thesonveyors and doors in the mannenset forth a suitable control system isprovided. It is deemed unnecessary to illustrate and describe thiscontrol system since a number of different kinds of systems may be-usedand the construction of which requires nothing more than mechanicalskill. Among the features of this invention is the use of a singlechambered annealing furnace for both radually heating and cooling thematerial going annealed, andthe automatically operable means providedfor automatically effecting the movement of the material into andthrough the furnace.

According to the provisions of the-patent statutes, We have explainedthe principle and mode of operation of our invention, and haveillustrated and described what we now charge openings, a front wall avertical heating and.with the moving blanks first upwardly with the rearwall a vertical cooling chamber, means at the front wall of the furnacefor, charging blanks laterally through said inlet opening, an endlessconveyor within the furnace for receiving the blanks and moving themfirst upwardly through the heating and then downwardly through thecooling chamber, and means for removing the blanks from said conveyorand directing them outwardly through said dis charge opening.

2. A furnace for annealing elongate blanks, comprising front and rear.walls provided respectively with horizontally disposed elongate inletand discharge openings, doors for opening and closing said openings, abattle forming with the front wall a vertical "heating chamber and withthe rear Wall a verti= cal cooling chamber, a conveyorwithin the furnacefor progressively moving blanks first upwardly through the heating andthen downwardly through the cooling chamber, 'and means coordinated withthe movement of said conveyor for operating said doors to permit blanksto enter the furnace through said inlet opening and to be dischargedfrom the furnace through said outlet opening.

3.1 A furnace for annealing elongate blanks, comprising front and rearwalls provided respectively with horizontally disposed elongate inletand discharge openings, means for opening and closing said inlet and disbaffle forming with the rear 'wall a vertical cooling chamber, aconveyor within the furnace for intermittently through the heating andthen downwardly through the cooling chamber a conveyor arranged adjacentthe inlet opening on the outside of the furnace for intermittentlyfeeding blanks to the furnace, and coordinated means for intermittentlyactuating said conveyors.

4. A furnace for annealing elongate blanks, comprising front and rearwalls provided respectively with horizontally disposed elongate inletand disch arge openings, a double walled bafile forming with the frontwall a vertical heating and with the rear wall a vertical coolingchamber, a conveyor arranged within and having aligned fingers extendingthrough said bafile, the outer ends of said fingers being provided withpockets for receiving blanks charged laterally with the furnace throughsaid inlet opening, and means for actuating said conveyor for movingblanks first upwardly through the heating and then downwardly throughthe cooling chamber,v

5. A furnace for annealing elongate blanks, comprising front and rearwalls provided respectively with horizontally disposed elongate inletand discharge openings, an inverted Ushaped bafile forming with thefront wall a vertical heating and with the rear wall a vertical coolingchamber, a conveyor arranged within and having aligned fingers extendingthrough said bafile, the outer ends of said fingers being provided withpockets for receiving blanks charged laterally into the furnace throughsaid inlet opening, means for actuating said conveyor for moving blanksfirst upwardly through the heating and then downwardly through thecooling chamber, and means adjacent to said discharge opening forremoving blanks from said conveyor and directing them to the dischargeopening.

6. A furnace for annealing elongate blanks, comprising front and rearwalls pro vided respectively with horizontally disposed elongate inletand discharge openings, a battle forming with the front wall a verticalheating chamber and with the rear wall a vertical cooling chamber, andan endless conveyor within and provided with blank-engaging meansextending through said baflle for progressively moving blanks firstupwardly through the heating and then downwardly through the coolingchamber of the furnace.

7'. A furnace for annealing metal, comprising front and rear wallsprovided respectively with inlet and discharge openings, a double-walledbaffle forming with the front wall a vertical heating and with the rearwall a vertical cooling chamber and havin vertical slots therein, aconveyor arrange within said bafiie and provided with blankengagingmembers extending through said slots therein, and means for actuatingsaid conveyor for moving blanks first upwardly through the heating andthen downwardly through the cooling chamber of the furnace.

8. A furnace for annealing metal, comprising front and rear wallsprovided respectively with inlet and outlet openings, a doublewalledbaffle having a refractory section forming with the front wall of thefurnace a vertical heating chamber and having a watercooled sectionforming with the rear wall of the furnace a vertical cooling chamber, aconveyor arranged within and having blankengaging members extendingthrough said hafile walls, and means for actuating said conveyor formoving blanks first upwardly through the heating and then downwardlythrough the cooling chamber of the furnace. In testimony whereof, wehereunto sign 0111' names.

GRANT B. SHIPLEY. HENRY ALINDER.

